A section of a host pipe is removed, a flange is placed at one end of the host pipe section and split sleeve halves are secured to one another and at one end to the flange to cantilever the split sleeve from the end of the host pipe. A deformed thermoplastic liner is drawn through the host pipe and split sleeve and reformed to its cylindrical configuration by introducing steam under pressure. Once reformed, the split sleeve halves are removed, the end portion of the rerounded liner is cut and an adapter flange is fused on the end of the cut liner portion. The split sleeve halves are reapplied about the rounded liner with the flange on the adapter bearing against an end face of the flanges of the split sleeve. A cylindrical section is welded to the adjacent host pipe section and a flange thereof is bolted to the distal end flange of the split sleeve whereby a permanent pressure sealed connection is provided between a lined host pipe section and a non-lined host pipe section.